Aspects of the present invention are directed to an apparatus for specimen handling during specimen preparation and analysis.
In manufacturing operations, very small components are often required to be analyzed via various analytical techniques. These techniques may include Transmission Electron Microscopy (TEM), Atom Probe Tomography (APT), Scanning Electron Microscopy (SEM), Focused Ion Beam (FIB), Scanning Probe Microscopy (SPM) and optical microscopy, amongst others and may be employed in various industrial and/or academic environments. In all cases, a high level of accuracy and precision in specimen manipulation is typically required.
A problem exists, however, in that the currently used apparatuses for specimen handling do not have accurate or precise specimen positioning systems. As such, the required high level of accuracy and precision in specimen handling is either unattained leading to specimen misalignment or attained only after several time consuming iterative corrections.
The lack of accuracy and precision provided by the currently used apparatuses may be caused by various factors. These include, but are not limited to, misalignment between a specimen and a holding device whereby the specimen is attached to the holding device at an angle as opposed to being straight on, a bend along the holding device and a rotation error whereby rotation of the holding device by a given angle for accurate specimen positioning cannot be guaranteed.
For example, in current apparatuses a flip stage is employed to rotate a specimen. Specimen alignment must be highly accurate lest the specimen be mounted improperly on the mounting. In the flip stage, the specimen is attached to a needle which is held between two plates. A back end of the needle is bent downwards to identify a first rotational position. With the needle in the first rotational position, an image of the specimen is taken such that its position can be determined. The needle is rotated toward a second rotational position such that the bent end now faces, for example, sideways to identify a 90° rotation. With the needle in the second rotational position, the specimen image is again taken such that its position can be re-determined. At this point, if the second specimen position is not horizontal, it can be inferred that the specimen is misaligned and that correction is required.
In the above-described scenario, the correction is time consuming and expensive. In addition, however, the flip stage itself may be highly inaccurate. The bending of the back of the needle can bend or damage the front end. Also, in order to be bent, the needle must be fashioned narrowly or otherwise less rigidly than it would otherwise be such that a risk of needle bending is increased. Finally, the bending itself along with the rotation are achieved by technicians who are prone to error.